Vitamin D supplements may ward off vision loss from an age-related eye disease in women younger than 75, research has shown.

Higher blood levels of the vitamin were associated with a significant decreased risk of age-related macular degeneration.

The condition, caused by progressive damage to the centre of the retina at the back of the eye, affects around two per cent of people over the age of 50 in developed countries.

More than 230,000 people in the UK are believed to be partially blind because of AMD.

Researchers in the US examined data on 1,313 women taking part in a large investigation of age-related eye disease.

They found that in women younger than 75, both vitamin D blood levels and consumption of the vitamin from food sources and supplements were linked to a reduced risk of early AMD.

Women with the highest vitamin D intake were 59 per cent less likely to develop the disease than those with the lowest.

But the association was only seen with vitamin D consumed in foods and supplements. Time spent in the sun did not affect risk levels, even though the most important source of vitamin D is its generation in the skin as a reaction to sunlight.

The top food sources of vitamin D among study participants were milk, fish, fortified margarine and fortified cereal.

The scientists, led by Amy Millen, from Buffalo University, New York, wrote in the journal Archives of Ophthalmology: “More studies are needed to verify this association as well as to better understand the potential interaction between vitamin D status and genetic and lifestyle factors with respect to risk of early AMD.”